I. Introduction
Distributed power generation (DPG) is expected to play an important role in the short and medium term design of the generation, transport and distribution system. This is due to the penetration of renewable generation units that allows to produce power, providing at the same time ancillary services (harmonic compensation [1], magnitude and frequency restoration [2],…) An engaging characteristic of the DPG systems based in renewable generation is that they help to decrease the emissions since the DPG units are placed near the power is consumed. On the other hand, the use of DPG increases the complexity of the whole system due to the coexistence of several systems with different characteristics (nominal power, output impedance, workload, transient response …)